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Mary Mahoney — 1940 US Census Record
Linked across censuses1940 United States Federal Census · St.-Clair-County, Illinois
Our Model Tree links this Mary Mahoney across the 1920, 1930 and 1940 US Censuses in St.-Clair-County, Illinois (XGBoost, ~Confirmed) — first a spouse (b.~1868), then head of a 4-person household.
Age 72
b. ~1868
Female
Spouse
Born: Missouri
Married
1940 Census Record Details
| Census Year | 1940 |
| Location | St.-Clair-County, Illinois |
| Surname | Mahoney |
| Given Name | Mary A. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 72 |
| Marital Status | Married |
| Birthplace | Missouri |
| 1935 Residence (City) | E. St. Louis |
| 1935 Residence (County) | St. Clair |
| Additional Details | |
| Class of Worker | 0 |
| Highest Grade | H 2 |
| 1935 Residence | Same place |
| Birth State | Missouri |
| Birth Country | United States |
| Birthplace (normalized) | missouri |
| Township / Ward | E St Louis |
| Est. Birth Year | ~1868 |
Household Members
Census records only state relationship to the household head.
Pairwise kinship is derived (~90–95% accurate), not recorded.
Step/blended families and boarders can break it.
4 people recorded at the same address in the 1940 census.
| Name | Relation to head | Relative to Mary | Age | Birth yr |
|---|---|---|---|---|
| Helen Mahoney | Daughter | — | 35 | ~1905 |
| John Mahoney | Head | — | 75 | ~1865 |
| George Mitchell | Other | — | 44 | ~1896 |
| Mary Mahoney | Spouse | — | 72 | ~1868 |
Census Appearances
1920
St Clair, …
Spouse, age 50
St Clair, Illinois · implied b. ~1870 — 7 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mahany |
| Given Name | Mary |
| Relationship to Head | wife |
| Sex | F |
| Color / Race | White |
| Age | 50 |
| Marital Status | Married |
| Birthplace | Missouri |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read | Yes |
| Can Write | Yes |
| Speaks English | Yes |
| Mother Tongue | English |
| Birth State | Missouri |
| Birth Country | United States |
| Birthplace (normalized) | missouri |
1930
St Clair, …
Spouse, age 60
St Clair, Illinois · implied b. ~1870 — 6 household members
●
Primary link
· ~Confirmed · 2 sources
XGBoost
Household
| Surname | Mahoney |
| Given Name | Mary H. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 60 |
| Marital Status | Married |
| Birthplace | Missouri |
| Age at First Marriage | 30 |
| Father's Birthplace | Ireland |
| Mother's Birthplace | Ireland |
| Can Read/Write | Yes |
| Birth State | Missouri |
| Birth Country | United States |
| Birthplace (normalized) | missouri |
1940
St.-Clair-County, Illinois
Spouse, age 72
St.-Clair-County, Illinois · implied b. ~1868 — 4 household members
| Surname | Mahoney |
| Given Name | Mary A. |
| Relationship to Head | Wife |
| Sex | F |
| Color / Race | White |
| Age | 72 |
| Marital Status | Married |
| Birthplace | Missouri |
| 1935 Residence (City) | E. St. Louis |
| 1935 Residence (County) | St. Clair |
| Class of Worker | 0 |
| Highest Grade | H 2 |
| 1935 Residence | Same place |
| Birth State | Missouri |
| Birth Country | United States |
| Birthplace (normalized) | missouri |
Model Tree
An inferred pedigree reconstructed from census links — up to 4 generations within the 1900–1950 window. Closer generations are built from household co-residence; deeper ones are bridged by following a relative to their own childhood census. Confidence compounds and weakens with each generation.
Our Model Tree links Mary Mahoney across 3 US Census years (1920, 1930 and 1940) in 2 locations, using XGBoost record linkage.
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This person
Anchor record
Mary Mahoney
Spouse · 1940 · age 72 · b. ~1868 · Illinois
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Confirmed / household (~0.90+)
Probable / derived (~0.65–0.89)
Candidate (<0.65, unverified)
Original Census Page
1940 US Federal Census — St.-Clair-County, Illinois
Open full size
1940 US Federal Census — St.-Clair-County, Illinois
Page Contents
40 people indexed on this census page (nara:1940:m-t0627-00881-00199)
| Line | Name | Age | Relation | Occupation | Birthplace |
|---|---|---|---|---|---|
| 41 | James Dawson | 17 | Son | New Worker | Illinois |
| 42 | Robert Dawson | 8 | Son | — | Illinois |
| 43 | Fred Casey | 52 | Head | Iron Worker | Illinois |
| 44 | Martha Casey | 48 | Wife | — | Illinois |
| 45 | Elaine Casey | 9 | Daughter | — | Illinois |
| 46 | Harry A. Bridges | 52 | Head | Yard Master | Illinois |
| 47 | Ellen Bridges | 51 | Wife | — | Illinois |
| 48 | Mrs Fred Summers | 20 | Daughter | — | Illinois |
| 49 | Thomas Bridges | 12 | Son | — | Illinois |
| 50 | John Mahoney | 75 | Head | — | Michigan |
| 51 | Mary A. Mahoney THIS PERSON | 72 | Wife | — | Missouri |
| 52 | Helen Mahoney | 35 | Daughter | Bookkeeper | Missouri |
| 53 | George Mitchell | 44 | Lodger | Bookkeeper | Illinois |
| 54 | George L. Mead | 61 | Head | Mail Carrier | Illinois |
| 55 | Elizabeth R. Mead | 47 | Wife | — | Illinois |
| 56 | Margaret Avault | 64 | Head | — | Illinois |
| 57 | Herbert Avault | 36 | Son | Chauffer | Illinois |
| 58 | Margaret Avault | 29 | Daughter | Stenographer | Illinois |
| 59 | Leo Jr. Versen | 44 | Head | Clerk | Missouri |
| 60 | Clara Versen | 45 | Wife | — | Illinois |
| 61 | Herbert Versen | 18 | Son | Stenographer | Illinois |
| 62 | Walter G. Versen | 14 | Son | — | Illinois |
| 63 | Robert E. Versen | 7 | Son | — | Illinois |
| 64 | Allen A. Versen | 2 | Son | — | Illinois |
| 65 | Scott Neilson | 55 | Head | Truck Driver | Illinois |
| 66 | Meta Neilson | 51 | Wife | — | Illinois |
| 67 | Edgar Neilson | 23 | Son | Salesman | Illinois |
| 68 | Alice Neilson | 11 | Daughter | — | Illinois |
| 69 | Alice Neilson | 79 | Mother | — | Iowa |
| 70 | John Brunkhorst | 65 | Head | Switchman | Illinois |
| 71 | Catherine Brunkhorst | 65 | Wife | — | Illinois |
| 72 | Joseph Graham | 61 | In Law | — | Illinois |
| 73 | George L. Mead | 61 | Head | Mail Carrier | Illinois |
| 74 | Elizabeth R. Mead | 47 | Wife | — | Illinois |
| 75 | John R. Mullen | 34 | Head | Auditor | Mississippi |
| 76 | Charlotte Mullen | 30 | Wife | — | Tennessee |
| 77 | John R. Jr. Mullen | 11 | Son | — | Illinois |
| 78 | John Mailele | 50 | Head | Waiter | Austria |
| 79 | Mary Mailele | 47 | Wife | — | Eire |
| 80 | John R. Jr. Mailele | 14 | Son | — | Illinois |
About This Record & Model Tree
This record was independently indexed by YourRoots from the 1940 United States Federal Census (NARA). Our Model Tree links this person across census decades using XGBoost-based record linkage, with per-link confidence scores. Household corroboration strengthens the signal when co-residents appear on the same census pages in multiple years.
Source: National Archives and Records Administration (NARA)